Vitamin C Helps Stem Cells Become Heart Cells

A big hope is that doctors will one day have an ample
supply of healthy human heart cells to transplant into failing
hearts, potentially offering an alternative to patients whose
only option is the transplantation of an entire donor heart.

Heart failure is a chronic condition in which the muscle
cannot pump enough blood to meet the body’s needs. It results
from damage to the heart muscle, often caused by heart attack.

“Once the heart muscle is dead, we don’t have a lot of
tools for that,” said study author Dr. Richard T. Lee, an
associate professor of medicine at Brigham and Women’s Hospital
and Harvard Medical School (news – web sites), both in Boston, Massachusetts.

Stem cells are so-called master cells that can develop into
various tissues in the body.

To date, the available method for coaxing embryonic stem
cells into heart cells has proved slow and labor-intensive,
according to Lee. “It’s not a very efficient process,” he told
Reuters Health.

But in the new study, published in the rapid track issue of
Circulation: Journal of the American Heart Association (news – web sites), Lee and
colleagues reported that vitamin C treatment readily coaxed
embryonic stem cells to convert into heart cells.

“Out of 880 compounds tested, only one of them actually
worked and it surprised us,” Lee said.

The stem cells had been genetically altered to produce a
bright green color if they converted to heart cells. Not only
did they turn green, they also began rhythmically beating,
results showed.

It’s not known how vitamin C achieves this effect or
whether it would work with human embryonic stem cells. Research
involving human embryonic stem cells is highly controversial
and restricted by the U.S. government.

Researchers also have been experimenting with transplanting
adult stem cells taken from thigh muscle or bone marrow into
damaged human hearts. But Lee said embryonic stem cells may
hold the greatest promise because they are the most versatile.

In a statement, Dr. Robert O. Bonow, president of the
American Heart Association, said that “although the findings of
this study are very preliminary with respect to their impact on
human lives, this line of research has enormous implications
for the future care of thousands of patients who develop heart
failure each year.

“Identifying mechanisms to transform stem cells into
differentiated heart muscle cells is an important step toward
clinical reality,” Bonow said.

SOURCE: Circulation
2003;10.1161/01.CIR.0000064899.53876.A3.